Senin , 17 Jan 2022 11:17:51
Interpreting blood eosinophil counts in health and obstructive lung disease

Yunus Çolak, Peter Lange

European Respiratory Journal 2022 59: 2102180; DOI: 10.1183/13993003.02180-2021


Asthma and COPD are prevalent chronic diseases characterised by presence of respiratory symptoms and airflow limitation caused by ongoing inflammatory process in the airways [1, 2]. While the clinical features are reversible or variable over time in asthma [1], they are more persistent and usually progressive over time in COPD [2]. The connection between these two common disorders has been debated thoroughly for many decades with proponents for both “splitting” or “lumping” them into either two distinct or one common entity [3–6]. The clinical heterogeneity of both conditions has also been recognised for a long time, and the fact that some patients show characteristics of both diseases simultaneously resulted in the official introduction of the asthma–COPD overlap label by the Global Initiative for Chronic Obstructive Lung Disease (GOLD) and Global Initiative for Asthma committees in 2014 [7].

Blood eosinophil count is a well-known measurement that is easy to implement both in hospital and GP settings as a useful biomarker for treatment response in certain types of COPD and asthma


  • Conflict of interest: Y. Çolak reports personal fees from Boehringer Ingelheim, AstraZeneca and Sanofi Genzyme outside the submitted work.

  • Conflict of interest: C. Lange reports grants and personal fees from Boehringer Ingelheim, AstraZeneca and GlaxoSmithKline outside the submitted work.

  • Received August 5, 2021.
  • Accepted August 12, 2021.